Chiang, Nonglak Meethong, 1 Paula T. Hammond, Yet-Ming Chiang,. Angela M. Belcher "Virus-Enabled Synthesis and Assembly of. Nanowires for Lithium Ton ...
A REVIEW ON BIOMIMETICS AND NANOTECHNOLOGY Tony V Varghese School of Nanoscience and Technology, National Institute of Technology, Calicut, India. tonyvalayil@gmail. com Abstract-
The
well-organized
multifunctional
structural
II.
compatibility of animals and plants found in our surroundings have attracted the interest of scientists working in many disciplines .There are different organisms in nature which are doing things in a similar way we humans need to do; the efforts to utilize these mechanisms by taking inspiration from these organisms resulted in a new and rapidly growing scientific effort called biomimetics. From the observations on these organisms it is found that their wonderful properties are all due to their micro or nano scale structural properties. In this article we present the utilization of some of these mechanisms found in nature to useful products for human with the help of nanotechnology and its tools.
Keywords- lJiomimetics, nanotechnology, templating, self assembly.
I.
INTRODUCTION
We are living in a world of wonderful things, which is able to give solutions for all the problems we are facing. All we need to do is observe it closely and learn from them and manipulate it in a suitable way to take advantage out of it. All the things in nature are formed after a long year of evolution process so copying or taking advantage out of it is a difficult job where comes the nanotechnology. Nanotechnology is the utilization/engineering of materials that are in nanometer range (one billionth of a meter). When the size of the material changes in to smaller scales such as nanometer the property of the material completely changes from its bulk properties; conductors become semiconductors or insulators, insulators become conductors, opaque material become transparent, etc. Properties at the bulk state are independent of the size and shape of the particle constituting them but at Nano level the size, shape and structural arrangement of the particle will be of much important; this is the main reason for their amazing behavior in Nano scale. It is the same case with the nature where the materials used are minimum; but the diversity is obtained by adding design to it otherwise in the structural variation. All the thing in nature are made mainly of five polymers polysaccharides, R NA, DNA, proteins and vitamins but how nature obtained this much diversity it is by minimizing the amount of materials used and by adding design to it.
978- 1-4673-0074-21 1 11$26.00 @201 1 IEEE
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BIOMIMETICS AND NANOTECHNOLOGY
The defmition given in Wikipedia for biomimetics is "Biomimetics is the examination of nature, its models, systems process and elements to emulate or take inspiration and translating them in to engineering design in order to solve human problems sustainably". This can be done in following three ways. (a) Replicating natural manufacturing methods as in the production of chemical compounds by plants and animals that is by replacing the conventional chemical method by organisms or in the process use the help of the organisms to make the result. (b) Mimicking the mechanisms found in nature, this is the process in which we will copy the mechanisms from different organisms using the help of suitable technologies in this there is no direct use of organisms are involved . Nanotechnology is mainly using for this copying mechanism. (c) Imitating organizational principles from social behavior of organisms like ants, bees, and microorganisms. This method is currently using in communication field, how this bees and ants are transferring their infonnation among them this can be implemented in communication field to minimize the amount energy used for the transfer of faster and easy data's among the interconnected units. This article is mainly concentrating on the first two methods of biomimetics because those are closely connected with nanotechnology. A.
Biological synthesis ofnanoparticle
Biomimetics can be utilized for the synthesis of nanoparticle which is an efficient and environment friendly process. Conventional methods of nanoparticle synthesis have many inherent disadvantages such as use of toxic solvents, generation of hazardous by-products, and high energy consumption. This can be overcome by replacing conventional methods by plants, algae, fungi and many more biological organisms for low cost and efficient synthesis of nanoparticles. These microorganisms are used as a catalytic agent or as passive agent for the size controlled production of nanoparticle. In this microorganisms are directly involved.
pressed in to the hole which will act as the support; finally
•
Micro·organism
Taxonomical group
Nanoparticle Location
Escherichia coli
bacteria
Cadmium Sulfide
Intracellular 1·5
Yeast (003)
fun�
Silver
Extracellular 1·5
Fusarium oxysporum
fun�
Gold
Extracellular 10·4()
lemon grass plant
plant
Gold
100·500
algae
Gold
9·10
Teflon is add on to the hole. Then it will be taken out from the template
and
exposed
UV
radiation
for
10hr.
From
platinum. To make the hairs highly directional hairs are t�eated . 300 better force of adheSIOn IS
with e-beam at an angle of found at an angle
300.
One more approach is available growing
carbon nanotube hairs. The carbon nanotubes developed are
extract
stiffer in nature therefore the force of adhesion produced is
Chlorella vulgaris
Figure 1.
B.
to
experiment they have found that these hairs break due �o la�k of strength in order to strengthen them they coat It WIth
lesser compared to previous method.
Biological replacements for nanoparticle synthesis
Mimicking the gecko foot structure Gecko's ability to climb on vertical walls and freely
moving on the walls has attracted the attention of many scientists. Mimicking this wonderful ability of gecko to build a robot which is a new idea developed from this; a robot which is able to climb even in vertical glass surfaces. With the help of sophisticated instruments like AFM and SEM scanning on the
Figure 3.
gecko foot structure scientists found that ability of gecko to climb
on
walls
is
due
to
the
Different steps in stooped nanohair synthesis
force developed by the
nanostructured fibers at the bottom. An image of the gecko foot structure is given in the figure below. From a close analysis they have found that the nano hairs are responsible for their behavior they are also highly directional in nature.
Figure 4.
Figure 2.
C.
Gecko feet structure from macrostructure to nanostructure
1) Synthesis:
It is difficult to grow nano hairs so it is
�
leaf is mainly is due to two properties found in a lotus leaf. A
making nano hairs is the development of an array of nano ho es
lotus leaf contain millions of nanoscale protrusions on there
on a silicon master plate with photolithography and reactIve etching.
trichlorosilane
These
nano
which
monolayer (SAM) coat
holes
will
are
develop
then a
coated
surfaces which will keep the water contact angle greater than
with
1500.
self-assembled
on the surface. Trichlorosilane is
molecule as droplets reduce wetting effect. Another effect found in lotus leaf are it very low water roll off angle the
removal of the hairs developed inside the nano holes. The nano
UV
surface contain a wax like hydrophobic substance which is
curable pre- polymer,
responsible for this effect. The hydrophobic wax present on the
flexible film (support), Teflon. First the nano holes are sprayed with
When the contact angle increses the surfacetension of the
water molecule preceeds and which will keep the water
sprayed in to the surface in order to make out the easy hairs are made of three materials
Superhydrophobic and self clean surface mimicking lotus leaf The superhydrophobic amd self cleaning effects in a lotus
made with help of making template; first step in the process of
ion
Stickybot a robot which can climb on vertical walls developed in Stanford University
surface
UV curable pre-polymer which will form the outer surface
which
will
help
to
keep
the
surface
clean
removing the dirt with the water rolling from the surface. The
of the hairs developed; then a flexible film of polymer is gently
hydrophobic wax will minimize the adhesive force between the
473
dirt and surface. The force of attraction between water drop and
for textiles, Lotus clay roofing tiles they make roofing tiles
dirt will be more than that of the surface and dirt.
and Mincor TX TT textile coating produce a self-cleaning coating for textiles.
negative template
PDMS
lift off positive replica
Figure 6.
Figure 7. Figure 5.
1) Synthesis:
Steps in developing artificial super hydrophobic surface.
Image of the self-cleaning paint developed by Lotusan
SEM image of the lotus leaf surface D.
First cast a mixture of liquid PDMS (poly
dimethylsiloxinate) with the catalyze on to a fresh lotus leaf.
Color shifting by mimicking butterfly and peacock The presence
of wonderful
colors
on
the
wings
of
The solidification will take place by keeping it at room
butterflies and peacocks are due to the presence of nano- sized,
temperature
of PDMS
transparent chitin and air layered structure. They can absorb
developed is peeled off from the lotus leaf. An anti-stick
and reflect certain light wavelength as pigments and dyes do to
for 24hrs.
The
negative
template
monolayer coating of trimethylchlorosilane is put on the
produce the color variation. Depending on the exact structure
template by evaporating technique. A second layer ofPDMS is
and interspatial distance between diffracting layers the color
performed on the negative template which willkeep at
can
800C
The
color
variation
is
rather
due
to
The
mimicking
of
the
microstructure
present on the butterfly wings are done by depositing an
automobiles, kitchen and bath and textiles. Some industries are such
changed.
l)Synthesis:
Some of the application ideas based on this strategy are making self-cleaning and water repellent surfaces for buildings, already making products based on this mimicking
be
microstructure than pigments.
and 25 min for solidification.
atomic layer thickness of AI203 on to the wing of a butterfly.
technique
The process is known as atomic layer deposition (ALD) which
as Lotusan Paint they produce self-cleaning coatings,
is carried out at
Green shield Fabricfinsh they produce multifunctional finishes
474
100°C.
The color can be controlled by the
interfaces. This will help in transitioning the change in light speed between the air and eye and hence minimizing reflection.
thickness of the replica and the material used to deposit on the surface.
Figure 9. Figure 8.
I)Synthesis: Mimicking the moth eye is a method o� producing antireflection coating; in orde� to produce �ntl reflecting surface flfSt the eye sample of fly IS fixed on �Iumma substrate. To make alumina growth on the surface atomic layer deposition (ALD) is performed with AI(CH 3)3 and de-ionized water as precursors; this is conducted at a pressure of 0.6 T?IT and at 800C. Ultrapure nitrogen (N2) was used as the carrymg gas for the precursor to the surface. The original fly �ye template is removed after the deposition process. The aluml�a substrate developed will then anneal at 5000C for 15to 20hr m a box furnace. The application based on this are development of anti-reflective, anti-glare, self-cleaning coating for solar cell collectors, windows, computer screens and to improve the conversion efficiencies of crystalline silicon solar cells. Industry using this technique is Moth eye and MARG films anti-reflective and anti-glare coatings.
Microscopic and SEM image of butterfly wings
In this experiment an increase in the coating thickness from 10 to 40 nm with a 10 nm interval, the reflected color shifted from original blue to green, yellow, orange, and eventually to pink. The application based on this strate�y . are paints for cars, buildings; production of fa�ncs, e!ectron�c display screens and in cosmetics. Compames u�mg this technique are Morphotex Structural Colored Fibers for Structural colored fibers, Mirasol display technology for electronic display screen, Chroma Flair Color-Shifting Paints for Color-shifting paints in automobiles. E.
SEM image of moth eye
Antireflective coating mimicking Moth eyes
Moth is types of butterfly found in nature their eyes have the property of ant reflectivity; this is use� to esc�p� from �he predators during night and to enable maximum vIsion durmg . night by absorbing maximum light. This won?erful b�havlO� of moth is due to the presence of nano SIze semlsphencal protuberances on the surface of the eye. The outer surfaces of moth corneal lenses are covered with a regular pattern of conical protuberances, generally 200-300 nm in height and spacing. These protuberances reduce light reflecti�n by creating a refractive index gradient between the alf-Iens
F.
Sensors by mimicking cilia ofanimals
Cilia is the hair like projection from the surface of a cell; which perform different function in different organisms such as in mosquitoes it act as different kind of order sensors to track human, for vampire bats it help in sensing he temperature, in vertebrate they present in the inner ear cells to convert sound
475
signals to electrical signals, for great white shark they present on the nostrils help to detect minute quantities of blood. The mechanisms of working of these cilia in all the animals are nearly the same. The sensitive detection is based on electrochemical methods when the analyte species are added to the nanotube sized hairs a change in trans-membrane current occurs which are measure of all the properties. 1) Synthesis : The main processes in the synthesis of the hair like sensors are the fabrication of the vertically aligned nano hairs and coating them with suitable silver alkoxy groups. It is done by creating an array of Nano holes in a sample and then aligning Nano hairs on these holes and coating them. The process involved in this process are track-etching by this process an array of nano holes are crated on a polycarbonate filters which is used as the template. In the track-etching process bombarding the solid material with a collimated beam of high energy nuclear fission fragments to create parallel damage tracks in the film. The damage tracks are then etched into mono-disperse cylindrical pores by exposing the film to a concentrated solution of aqueous base. Electroless plating method used to deposit the Au within the pores of these membranes. Template membrane is first sensitized by immersion into a SnCI2. The sensitized membrane is then immersed into AgN03 solution to produce to have a silver alkoxy coating. G.
M13
J Virus/l-� 4
I
Assembly Engineering Macroscopic Self Assembly of Virus
Genetic modification for storage process ��
Genetic modification can be done in organisms to for both data storage and forming anode and cathode in lithium ion battery. All the information's in living organisms are stored on DNA; the information in DNA is stored as code in amino acid sequences of proteins. To store data on a DNA there are two methods available first method is the one in which constructing a DNA sequence reflecting the code. These codes are then inserted on to the oligonucleotide sequences redundantly into multiple locations in the non-coding regions of the B. subtilis genome. When want to read out the messages at a later time, use the primers to amplify the coded regions. Another method for data storage is that using A-DNA they are fluorescent in nature immobilize them and scaffold them in to an array of Nano electrodes. To store the digital information in to the DNA they are photo bleached using Argon laser beam.
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Hllh Power LIthIuIt 101 bIIery Cathode a-ftPO, tem�ate4 'rim aanowire
In lithium ion battery for storing the chemical energy gene modified virus are used as anode and cathode. The gene inside a virus (Ml3), which is a bacteriophage, is manipulated in order to coat it with cobaltoxide and gold. The coating is given to make them conductive. The virus then self-assembled to form an anode. The cathode is made in the same way as that of the anode in this case the manipulation is done in order to coat it with iron-phosphate and to bind it with carbon nanotube to form conductive cathode.
SWIn'
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liomolKIIl1! recogllitiol lid attJchmtnt " IttIplate4 IIIIS to SWNT
Figure 10. Anode and Cathode of the virus enabled lithium ion battery developed in MIT
476
III.
CONCLUSION
We have explained so far how nanotechnology can be utilized for mimicking the wonderful features in nature. We have found that nanotechnology is a well-developed tool for biomimetics. But the problem with nanotechnology scientists are great concerned is the environmental problem that can be created by the nanoparticle we are producing. There are lots of papers based on the toxicology effects which can be created from nanoparticle to both humans, other living organisms and to the environment. But a close observation in nature shows that most of the processes in nature are occurring at nano scale with the help of nanoparticles. But how nature is doing nanotechnology safely scientists have found a solution for that by observing the sulfur reducing bacteria. In sulfur reducing bacteria during their reduction they produce nanoparticle in to water after the process they produce a protein in to the same this protein helps to agglomerate these nanoparticle and help to remove them from water. So we can conclude that nature is nano it has going its own method of doing it. Biomimetics using nanotechnology is a great technology for reproducing these effects for our benefit. It is better to ask the question how nature doing things when we are planning for new designs which will help to fmd out new designs from which are more efficient, more environment friendly and low power consuming.
REFERENCES
477
[1]
P Ramachandra Rao Biomimetics
[2 ]
By Tae-il Kim, Hoon Eui Jeong, Kahp Y. Suh, and Hong H. Lee. Stooped Nanohairs: Geometry-Controllable,Unidirectional, Reversible, and Robust Gecko-like Dry Adhesive
[3 ]
Manhui Sun Chunxiong Luo, Luping Xu, Hang Ji" Qi Ouyang,Dapeng Yu and Yong Chen"/", Artificial Lotus Leaf by Nanocasting
[4]
L. P. Biroa,K.Kertesza,Z. Vertesya,Zs.Balintb Photonic nanoarchitectures occurring in butterfly scales as selective gas/vapor sensors
[5 ]
Jingyun Huang!,2, XUdongWang! and Zhong LinWang! Bio- inspired fabrication of antireflection nanostructures by replicating fly eyes
[6]
Punit Kohli, Marc Wirtz, Charles R. Martin Nanotube Membrane Based Biosensors
[7]
Yingchen Yang, Nannan Chen, Craig Tucker, Jonathan Engel, Saunvit Pandya, Chang liu. Artificial hair cell sensor to artificial lateral line system: development and application
[8]
Willem A Germishuizen , Christoph Walti, Rene Wirtz, Michael B Johnston, Alexander G Davies, Michael Pepper, and Anton P J Middelberg "Data storage using DNA"
[9]
Electrodes Ki Tae Nam,!,4 Dong-Wan Kim,! Pil J. Yoo,Chung- Yi Chiang, Nonglak Meethong, 1 Paula T. Hammond, Yet-Ming Chiang, Angela M. Belcher "Virus-Enabled Synthesis and Assembly of Nanowires for Lithium Ton Battery"
